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Luminaires with high in-rush

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    Luminaires with high in-rush

    I'm working on an installation of luminaires that have electronic power supplies that create a large inrush current at turn-on. A typical string of lights on a 20A branch circuit (277V) would create an inrush of 300A for 8.3ms (1/2 cycle).

    Is a high-inrush type of CB the best solution (assuming I can't change the luminaire power supply, split the circuit, etc.)?

    What CB brands and types are easiest to find?

    I have been looking at a Heinemann AMR type (one of their curves goes to 30X rating for inrush), BUT it seems everyone only stocks them in UL1077 types rather than UL489. I need UL489.

    I'm seeing more and more solid state lighting and some have low inrush and some have high inrush - it seems that this must be getting to be a more common problem as lighting migrates to electronic drivers.

    Thanks for any thoughts.

    Welcome to the forum!

    I wonder whether an HACR breaker would suffice, or even a standard SWD rated one?
    Master Electrician
    Electrical Contractor
    Richmond, VA


      look at the 'high magnetic' version of square D QO, for example QO120HM for 20 amp single pole.


        oops, i reread and saw the application is 277v. I know the square D EDB breakers for the NF panelboards are rated for HID lighting (high inrush)

        Even if you got the Eaton AMR breakers you want, what are you going to put them in?